Yes, but you will probably need to change the bell housing. I put an SM 420 in my 1 Ton, but I had to change the bell housing and get my forward dive shaft shortened. You may also have to change the starter and flywheel.
I believe the easiest way to solve all of this, since you may need engine work to start with, is to find another 235 with an SM 420 already on it from another later model truck. That is what I would do if I was to do it again.
